File storage, mainly. I have 2 NAS devices (one Synology I picked up in 2014, and an Unraid device I just built a couple months ago) - the former holds 13TB and the latter currently holds 35TB with plans to bring it to 100TB as I get money for more drives.

The Unraid system has a Youtube-dl instance running to auto-pull videos from the channels I follow, and I also run my Plex server from it. The Synology only has a Git server on it that I use to keep local copies of repos that I store on GitHub, along with personal projects that I’d rather not publish (even as private repos) in the cloud.

It works, at least. The only issue I’m seeing is that if I try to follow ‘sublemmies’ (or whatever the Lemmy equivalent for a subreddit is called) from certain other federated servers, they just sit in ‘subscribe pending’. A fediverse that creates a lot of friction when spreading out beyond your local instance is a bit of a bummer.